Operating mechanism for plungers of caulking guns



Nvf14'f1950 w. P. PETERSON 2,530,359

l OPERATING MECHANISM FCR PLUNGERS 0F CAULKING GUNS Filed March 20, 1948 Gttorneg U Patented Nov. 14, 1950 OPERATING MECHANISM FOR PLUN GERS F CAULKING GUNS Wilburv P. Peterson, Independence, Mo., assignor to Northeast Tool and Die Works, Inc., Kansas City, Mo., a corporation of Missouri Application March 20, 1948, Serial No. 16,110

3 Claims.

This invention relates to caulking guns, and particularly to guns for dispensing the caulking material from a cartridge through a nozzle of the gun.

The invention is particularly directed to a gun having a magazine semi-circular in cross section adapted to receive the cartridge in which the plastic or other material is contained to be ejected through the gun nozzle by pressure -of a plunger expelling the material therefrom and a frame connected to the barrel having a hand grip and having manually operated mechanism adapted toextend the plunger forwardly in the barrel, holding of the plunger extended in the barrel and for release of the -plunger so that it may be withdrawn for placement of another cartridge in themagazine; n

The principal objects of my invention are to provide a magazine or` trough for thecartridge containing plastic material; to provide a plate surrounding the plunger rod for holding the rod in extended position and having an arm or lever extending below the frame of the gun and parallel to the lever of the handle for easy access of the operator, for releasing the plate from gripping contact with the rod, and to provide spring means on each side of the holding plate surrounding the rod, the forward spring being of stronger tension than the back spring for Vexerting pressure on the holding plate to hold the plate in engaging relation with the rod when the device is in normal position.

`Other objects of the present invention are to provide a magazine for a cartridge containing plastic material which may be easily applied to and vremoved from the magazine; to provide a device of this character operable by one hand of the operator and t0 provide a device of this character extremely simple, economical to manufacture, and efficient in operation.

In accomplishing these and other objects of the present invention, I have provided improved details of structure, the preferred forms of which are illustrated in the accompanying drawings, wherein:

Fig. 1 is a perspective View of my caulking gun.

Fig. 2 is a longitudinal central section through the gun.

' Fig. 3 is a longitudinal central section through a part of the gun, particularly illustrating the Fig. 5 is a top plan sectional view of the working mechanism of the gun.

Referring more in detail to the drawings:

I designates a. gun embodying the features of my invention comprising a magazine 2 here shown to be elongated and semi-circular in cross section, having caps 3 and 4 rigidly secured to its respective ends by welding or other suitable means, The magazine 2 is adapted to receive a cartridge 5 (Fig. 2) containing a plastic or other material 6 to be used in the gun. The caps 3 and 4 are provided with flanges l and 8 for retaining the cartridge in the trough 9 of the magazine during operation of the gun.

.Rigidly secured to the rear face 0f the cap 3 by welding or other suitable means is a frame 9 having a handle or hand grip I0 comprising a single sheet of metal doubled on itself to provide a rounded back portion II and two parallel side portions I2 and I3. The forward end of the frame 9 is flared outwardll7 forming flangesl I4 on each of the side pieces I2 and I3 for fastening the frame to the cap 3. The forward portion of the hand grip I0 is open and pivotably mounted therein by a bolt lI5 0r the like is a lever I6. The lower end of the handle I0 is provided with inturned flanges or lugs I1 to lend rigidity to the handle structure and provide a stop for the lever I6. The underneath portion of the frame 9 is also open and provided with inturned angesor lugs I9 to strengthen frame and also form an abutment against which a lug 20 on the forward portion of the lever I6 is adapted to engage and thus provide a stop for forward movement of the lever I6. The lever I6 is trough-shaped and has a rounded front portion 2| (Fig. 1) and the lug 20 is formed by severing and bending forwardly a portion of the lever.

The cap 3 is centrally bored as indicated at 22 (Fig. 3) and the rear portion of the frame is also provided with an opening 23, the opening being formed by inward punching of the rear portion of the frame forming a boss 24, Extending through the openings 22 and 23 and adapted to slide therein is a plunger rod 25. Rigidly se'- cured on the forward end of the plunger rod is a disk 26, the disk being slightly smaller in diameter than the flanges 1 and 8 of the caps of the magazine and also slightly smaller than the inside of the cartridge 5. The plunger rod 25 extends outwardly thro-ugh the opening 23 of the frame, the outer end being turned laterally to provide a handle 21.

Surrounding the plunger rod 25 Within the hand grip are a plurality of feeding plates 28,

two of such plates being here shown and between these plates and the boss 24 are washers 29. Also surrounding the plunger rod 25 forwardly of the plates 28 is a plate 30 for holding the rod as it is fed forwardly in the magazine, one end of which extends through the lower open portion of the .frame 9 rand is Aturned forwardly and downwardly forming a finger portion 3|. Also surrounding the rod 25 between the holding plate 3B and feeding plates 28 is a coil spring 32. The spring 32 normally pressing the plates 28 back to the limit of Itheir movement or against the washers 29 and in turn the boss 24. A coil spring 33 is provided for surrounding the plunger rod 25 between the plate v3|) and the rear face 34 of the cap 3. The spring A33 is stronger than the spring 32 to exerta greater pressure on the holding plate to hold the plate in biting or gripping relation on the rod 25when the gun is in normal position. A pin 35 extends transversally through the hand grip l near the holding plate underneath the plunger Arod 25 providing a fulcrum or pivotal point for the plate 30.

A spout 36 is ycentrally located in the cap 4 through which the material 6 is forced from the cartridge upon operation of the plunger rod 25.

Operation of a device constructed and assembled as described is as follows:

The plunger rod is withdrawn from the magazine through the hand grip by backward pres- `sure on the linger portion 3| of the plate .38, the plate being fulcrumed von .the pin will move the upper end forwardly against the ten- .sion of the spring r33 thus releasing the plate 30 'from gripping engagement with the rod. Back- .ward pull on the yhandle 2l of the rod will move the plunger rod .with 4its disk baci: tothe cap 3. The vcartridge vl5 may then be inserted in the magazine. The forward end of the cartridge is provided with a central open portion (not shown) lfor engagement with the spout 38 which extends inwardly a slight distance from the cap 1.4 as illustrated at 3l, Figs. l and 2. The rear end of the cartridge 5 is provided with an .end 38 adapted to slide alongthe inner surface of .the cartridge. The end'is anged as indicated at 39 (Fig. 2) for receiving the disk 28.

The upper end of the lever I6 is provided with .an upstanding lug. 40 adapted to engage against the rear face of the plates 28. The plates 28 aresubstantially `rectangular in shape and operation of the lever l5 will cause the lug 40 to engage thelplates 28 and cause them to grip the rod and move themforwardly. Tension of the spring .32 will overcome the tension ,of .the spring ,33 releasing the plate3ll so that the plunger will move forwardly in the magazine, the plates 28 gripping the rod when the lug 48 exerts pressure on the lower end thereof. When the lever |6 is released the spring 33 .again overcomes the tension of the springs 32 andthe plate 13B will grip the rod'to hold the rod in its rforwardly extended position. Operation of the lever is thus continued forwardly and backwardly until the plunger is fully extended in the magazine and the material has been extruded from the cartridge 5. The plate 30 is then released by backward vpressure on the linger portionl 3| and the rod may again be removed from the cartridge and magazine by backward pull on the handle 2l' so that the empty cartridge may be removed and a new one placed in `the ,magazine .A hairpin spring 4| is providedto engagethepin l5 of lthe lever-,2| with-itsfarms @Landau-en- 4 gaging the hand grip ll and lever 2| respectively ito hold the lever 2| normally in forward posiion.

It will be obvious from the foregoing that I have provided an improved caulking gun which may be operated by one hand of the operator and which has few moving parts.

What I claim and desire to ,secure by Letters Patent is:

1. In a caulking gun, the combination of a magazine, a hollow handle secured to the magazine, said handle being open toward the front, a plunger operating rod extending out of the magazine `and through said handle, a movable feeding plate within the handle loosely surrounding the rod, an apertured holding plate within the handle between the feeding plate and the rear end of the magazine and closely surrounding the rod, aiixedfulcrum for the holding plate Within the handle below the rod, a spring surrounding the 'rod between the holding plate and therear end of the rrragazine `tending to swing the holding plate about its fulcrum into engagement with the rod for binding said rod against rearward lrnovement, a compression spring surrounding the rod Fbetween the feeding plate and holding plate,.said compression spring having ends engaging the feeding plate and holding plate and acting to ,urge the feeding plate `away from the holding plate, an operating lever pivoted within the handle for canting vthe feeding plate` and moving it forwardly to feed the rod, and means whereby `the holdingvplatermay be swung out of binding engagement withthe rod.

2. In a caulking gun, the combination of a magazine, a hollow handle secured to the rear end of the magazine, saidhandle being open toward the front, a plunger operating rod extending out `of the magazine and through said handle. a movable feeding plate within the,handle loosely surrounding the rod, an apertured holding plate .within the handle between the .feeding plate and the rear end of the magazine and closely surrounding the rod, a pin extending .transversely a .through the .handle below the rod forming a ful- Lorum for the holding plate, a spring surroundin g therod between the holding plate and the rear end of the magazine tending to swing the holding plate about its fulcrurn intoengagement with the rod for binding said vrod against rear- .ward movement, a compression spring surrounding the rod between and actingon -the feeding plate .and holding plate tending to force the feeding plate toward the rear of the handle, a lever pivoted within thehandle and movable toward it,.said lever having .an extension .engageable with the feeding plate for canting the feeding plate ,andmoving it forwardly tofeedthe rod, and means .whereby the holding plate may be swung out of binding engagement with the rod.

3. In .a caulking gun, the combination of a magazine for receiving acartridge containing ka caulking material, a hollow handle secured tothe rear end of the magazine, said handle being open toward the front, a plunger operating .rod extending .out of the magazine and through said handle, a movable feeding platewithin the handle and having an opening loosely surrounding the rod, an apertured holding plate withinthe handle between the feeding plate and the rear end of -the magazine and having an opening closely surrounding the rod a fixed-fulerum for the holding plate within the handle below the rod, a .spring surrounding the rod between the holding plate and the rear end of the magazine tending to swing the holding plate about its fulcrum into engagement Withvthe rod for binding said rod against rearward movement, a compression spring surrounding the rod between and acting on the feeding and holding plates tending to 5 swinging the upper portion of the holding plate 15 6 forwardly out of binding engagement with the rod.

WILBUR P. PETERSON.

REFERENCES CITED The following references are of record in the file of this patent:

UNITED STATES PATENTS 10 Number Name Date 1,986,166 Schneider Jan. 1, 1935 2,305,238 Coates Dec. l5, 1942 2,367,346 Good Jan. 16, 1945 2,420,203 Sherbondy May 6, 1947 

